I’m using 3x Raspberry Pi 3 with HiFiBerry Digi/Digi+
Multiroom works great and i’m satisfied with it!

What I could not find in Forum & Co:

My AMP is only receiving 2.0 PCM while I’m using squeezebox server and squeezelite as player. HiFiBerry or HDMI does not make a difference.
Is it possible to get 5.1 speaker output when using squeezebox server for multiroom and squeezelite as players?

I tried some things with the command line options and ALSA Parameters, but I have no idea of what i’m doing there.
Within Kodi, DTS and DolbyD in 5.1 works fine with TIDAL-Lossless streams. No problem on that side.